From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1518C433EF for ; Sun, 13 Mar 2022 08:52:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234056AbiCMIyF (ORCPT ); Sun, 13 Mar 2022 04:54:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38342 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229379AbiCMIyB (ORCPT ); Sun, 13 Mar 2022 04:54:01 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3C75238; Sun, 13 Mar 2022 00:52:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=XxBAm++QJgtGU16ffhunyrTU2NHDo5CknXs8koZZv2Y=; b=iWI8oFWKPrDvTTvon1p2L1CZSP 6KsP6t8vSsTn8h7vwkkVxYaB3HpCZNVntkjVS7DDOvISzoecPNFEgFkIm2vlhnjs9wtLFjFs0o1fj eQPxEo1BjdynXFkD4nF9rLMcU9VgPH0y7+iFrvABalSMoY7UJF2KTuo7owH8x6UlggTi9GBEezeNe PmIr4vMioNXdXTUT43fLGdtOPV8WE76SBERfy7t7LNVWS88WU+hdG0wrWKjf6qUEhCZSXNZakaOG/ tQB9QFtIuswz7Uuf/XjNTsZPB3bfWhwx6BTW9S9wfgQmXWszlNGUMO803v50cmebT6B5b3IQNiGfw LZmxn9dA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nTJxY-000TQE-Ph; Sun, 13 Mar 2022 08:52:16 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id 892E3987D0D; Sun, 13 Mar 2022 09:52:14 +0100 (CET) Date: Sun, 13 Mar 2022 09:52:14 +0100 From: Peter Zijlstra To: Alexei Starovoitov Cc: Kumar Kartikeya Dwivedi , X86 ML , joao@overdrivepizza.com, hjl.tools@gmail.com, Josh Poimboeuf , Andrew Cooper , LKML , Nick Desaulniers , Kees Cook , Sami Tolvanen , Mark Rutland , alyssa.milburn@intel.com, Miroslav Benes , Steven Rostedt , Masami Hiramatsu , Daniel Borkmann , Andrii Nakryiko , bpf Subject: Re: [PATCH v4 00/45] x86: Kernel IBT Message-ID: <20220313085214.GK28057@worktop.programming.kicks-ass.net> References: <20220309190917.w3tq72alughslanq@ast-mbp.dhcp.thefacebook.com> <20220312154407.GF28057@worktop.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 12, 2022 at 05:33:39PM -0800, Alexei Starovoitov wrote: > During the build with gcc 8.5 I see: > > arch/x86/crypto/crc32c-intel.o: warning: objtool: file already has > .ibt_endbr_seal, skipping > arch/x86/crypto/crc32c-intel.o: warning: objtool: file already has > .orc_unwind section, skipping > LD [M] crypto/async_tx/async_xor.ko > LD [M] crypto/authenc.ko > make[3]: *** [../scripts/Makefile.modfinal:61: > arch/x86/crypto/crc32c-intel.ko] Error 255 > make[3]: *** Waiting for unfinished jobs.... > > but make clean cures it. > I suspect it's some missing makefile dependency. Yes, I recently ran into it; I've been trying to kick Makefile into submission but have not had success yet. Will try again on Monday. Problem appears to be that it will re-link .ko even though .o hasn't changed, resulting in duplicate objtool runs. I've been trying to have makefile generate .o.objtool empty file to serve as dependency marker to avoid doing second objtool run, but like said, no luck yet. > and: > vmlinux.o: warning: objtool: ksys_unshare()+0x626: unreachable instruction > which stays even after make clean. Humm, I shall have to dig out gcc-8.5 then. > The rcu "false positive" is still there that causes > sporadic hangs during the boot. I've merged fix for that yesterday, shall respin this ibt tree to include that. > The test_progs shows: > Summary: 228/1122 PASSED, 4 SKIPPED, 6 FAILED > (when I remove one test) > > That test is actually crashing the kernel: > ./test_progs -t mod_race Argh, I wasn't seeing crashing, I'll prod with sharp stick.